Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Luminance enhancement structure for reflective display devices

a display device and enhancement structure technology, applied in the field of illumination enhancement structure for reflective display devices, can solve the problems of reduced brightness of display devices, inability to meet brightness requirements, and inability to achieve satisfactory brightness, so as to reduce total internal reflection, increase the overall reflectance, and increase the brightness of display devices

Active Publication Date: 2013-05-07
E INK CORPORATION
View PDF69 Cites 39 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

The luminance enhancement structure in this patent increases the amount of light that reflects from a display device, which makes it brighter. The design also causes some of the light to reflect at certain angles, resulting in a more pronounced enhancement of brightness within a specific viewing angle.

Problems solved by technology

The lack of satisfactory brightness is often a concern for electrophoretic display devices.
Total internal reflection inevitably would occur with electrophoretic display devices because a display device usually has components of a high refractive index.
This total internal reflection phenomenon may result in a loss of about 30-50% of the scattering light, thus causing reduction in brightness of the display device.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Luminance enhancement structure for reflective display devices
  • Luminance enhancement structure for reflective display devices
  • Luminance enhancement structure for reflective display devices

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

I. Definitions

[0023]The technical term “total internal reflection” used in this application refers to an optical phenomenon that occurs when a ray of light strikes a medium boundary at an angle larger than the critical angle (defined below) with respect to the normal axis to the surface. This can only occur where light travels from a medium with a higher refractive index to one with a lower refractive index.

[0024]Generally speaking, when a ray of light crosses a boundary between materials with different refractive indices, the light will be partially refracted at the boundary surface, and partially reflected. However, if the angle of incidence is greater than the critical angle, the light will stop crossing the boundary and instead be totally reflected back.

[0025]The critical angle is calculated based on the equation of Snell's law: C=sin−1 (n2 / n1) wherein n1 and n2 are the refractive indices of the two different media, with n1 being the higher refractive index and n2 being the lowe...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
thicknessaaaaaaaaaa
thicknessaaaaaaaaaa
top angleaaaaaaaaaa
Login to View More

Abstract

The present invention is directed to luminance enhancement structure for reflective display devices. The luminance enhancement structure comprises grooves and columns, wherein said grooves have a triangular cross-section and a top angle, and said grooves and columns are in alternating order and in a continuous form in one direction. The luminance enhancement structure not only can reduce the total internal reflection, but also especially can enhance the on-axis brightness of a display device.

Description

[0001]This application is a continuation-in-part of U.S. patent application Ser. No. 12 / 397,917, filed on Mar. 4, 2009, which claims the benefit of U.S. Provisional Application Nos. 61 / 141,162, filed Dec. 29, 2008, and 61 / 035,646, filed Mar. 11, 2008, which are incorporated herein by reference in their entirety.FIELD OF THE INVENTION[0002]The present invention is directed to a luminance enhancement structure for reflective display devices. The structure not only can reduce total internal reflection, but also can further enhance the on-axis brightness of a display device.BACKGROUND OF THE INVENTION[0003]The lack of satisfactory brightness is often a concern for electrophoretic display devices. Total internal reflection inevitably would occur with electrophoretic display devices because a display device usually has components of a high refractive index. Due to the component having a higher refractive index (e.g., about 1.5) than the air (which has a refractive index of about 1) surrou...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(United States)
IPC IPC(8): G02B26/00G02F1/29G02F1/1343G09G3/34G09G3/04G02F1/03
CPCG02F1/133553G09G3/344G02F2001/133507G09G2320/0233G02F1/133507
Inventor LIN, CRAIG
Owner E INK CORPORATION
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products